Pedicle screw technique has been developed quickly since its introduction in 1980s and has been widely applied to surgical treatment on affections such as spinal degeneration, spondylolisthesis, spinal stenosis, vertebral fracture, malformation, metastatic tumor of bone, spinal unsteadiness and the like. At present, pedicle screw, one of the internal fixation instruments, is most widely used in spinal surgeries. However, the process of screw placement needs repeated fluoroscopy during actual operations. Particularly, radiation exposure time is apparently increased in minimally invasive operations, such as through a small incision or percutaneous way. Currently, damage of small dose of repeated x-ray exposure to patients and medical care personnel is not clear, but to reduce the x-ray exposure to the patients and medical care personnel during spinal surgeries has become a consensus of all spinal surgeons currently.
Positioning for intra-operative screw placement depends on an X-ray unit presently, which requires repeated intra-operative fluoroscopy and adjustment. During small incision screw placement, more repeated fluoroscopy is needed on the x-ray dose. Therefore, the x-ray exposure to the patients and medical care personnel is apparently prolonged and the operating time is prolonged. Moreover, intra-operative fluoroscopy also increases the probability of surgical incision infection. A latest robot system does not need fluoroscopy during the screw placement process, but a metal positioning screw needs to be embedded before surgery; meanwhile, CT scanning is required. The x-ray exposure to the patients is not reduced and extra pain of placing the positioning screw will be gained. In addition, the robot is expensive, which is used by few hospitals all over the world, and cannot be popularized.